For weeks now, we've heard that the title of 'Arrow' season 2's 19th installment had been kept under wraps to shield a special surprise, and even after executive producer Marc Guggenheim revealed it as "The Man Under the Hood," our curiosity remained intact. Now it seems the episode in question will set up the 'Flash' spinoff by introducing its supporting S.T.A.R. Labs cast, including DC characters Vibe and Killer Frost!

Reddit users seemingly obtained a call sheet for production of the episode, which included Danielle Panabaker's Caitlin Snow and Carlos Valdes' Cisco Ramon, both early incarnations of Killer Frost and Vibe we know to be featured in 'The Flash' should The CW take it to series.

Guggenheim confirmed this information in a statement (via TV Line),:

The idea of bringing in those characters really, really appealed to us because it allowed us to honor our original intention [of] doing something 'Flash'-related around Episode 19 or 20 without … basically paying Grant Gustin to sit around with his eyes closed/unconscious the whole episode. ... This episode is really cool. It allows us to further flesh out the 'Flash' universe on 'Arrow.'

Grant Gustin's Barry Allen was not among the names on the call sheet, which Guggenheim explained is because Allen won't likely awaken from his coma until 'The Flash' premiere, though it stands to reason "The Man Under the Hood" might either take place in Central City or at least see some kind of update on his status.

Originally, the 20th episode of 'Arrow' season 2 was to return Barry Allen to the forefront as a backdoor pilot to his own potential series, though The CW since decided to film a separate pilot for 'The Flash' altogether, set photos of which we've already seen. ‘The Flash’'s cast also includes Tom Cavanagh as Harrison Wells, Candice Batton as Iris West, daughter to Jesse L. Martin’s Detective West, along with ‘The Vampire Diaries‘ star Rick Cosnett as Central City Police transfer Detective Eddie Thawne, who likely corresponds to ‘Flash’ comic villain and time traveler Eobard Thawne. However, none beside Panabaker and Valdes have been confirmed to appear in "The Man Under the Hood."

Well, what do you think? 'Arrow' season 2 may yet have more surprises in store, but are you excited to see some of 'The Flash''s supporting cast introduced in "The Man Under the Hood"? How would you like 'Arrow' and 'The Flash' to interact if The CW picks up the latter to series?

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